This invention relates to data imprinting devices, for cameras, which imprint data on pictures taken including the date when the picture is taken. More particularly, the invention relates to a data imprinting device having an integrated optical system which reduces the number of elements in the camera and thereby increases productivity.
Conventional imprinting devices include a compound prism lens element, mounted in a shaft of a camera body, and a diaphragm element mounted within the shaft a fixed distance from the prism lens element. A spacer support member is required to mount the diaphragm member a correct distance from the prism lens for a gathering a light beam and controlling properly controlling an amount of light passing therethrough. This installation of the spacer support member and the alignment of the respective parts increases production time and costs.
At times, it is desirable to imprint data on multiple types of screens or imprint multiple data on one screen. In conventional devices, imprinting data on the film at different locations requires multiple optical members. Each optical member has to be accurately placed in the camera so that the data is properly focused and clearly imprinted on the film for each screen mode. Generally, the installation process is very time consuming.
Imprinting data on different locations at the same time requires additional control mechanisms. These are needed to account for the differing amounts of light and flash time. This adds additional elements to the camera. More specifically, Japanese Laid Open Patent Application No. 58-79235 discloses a filter disposed between the light source and the optical members to adjust the amount of light to obtain proper exposure. In this case, the filter has to be supported by another element. The same drawbacks exist in this prior art.
Other conventional devices having a plurality of optical members, a control mechanism for each optical member is required. The control mechanism adjusts an amount of light from a light emitting source to obtain proper exposure when imprinting data. The control mechanism is an electrical control device which operates during each exposure. However, the control mechanism requires additional data and hardware elements to calculate a correction value than a normal camera does. Increases in the production cost of the camera result. Additionally, it is impossible to simultaneously imprint data at multiple positions using devices of the prior art.